It was more than just software. AOA sensors can malfunction. The
mere fact they made AOA sensor redundancy optional opened the door
to this fiasco.
The other issue that doesn't get enough attention is pilot
training/proficiency. When automatic systems hit boundary
conditions, it helps to know what your options are.
bp
<part15sbs{at}gmail{dot}com>
Nobody mentions the Airbus angle of attack sensors that
caused a Lufthansa to almost crash.
They had the luxury of altitude or it would have been a
similar disaster.
According to the interwebs, AOA sensors have caused 50
similar type of situations in the past five years over a
wide spectrum of aircraft.
Apparently one brand fails more than another common
brand.
Sensor failure happens. Software can make it less or
more of a problem. Training can make it non fatal.
The MCAS software was to blame here.
I also do not believe that any automated control input
system should be stronger than the pilots.
Moreover, if the pilots are putting in an input opposite
that of an onboard system, something should disconnect the
onboard system automatically I would think.
Imagine getting into a wrestling match with your Tesla
that decided to take an off ramp.
Sent: Tuesday, November 12, 2019 9:22 AM
Subject: Re: [AFMUG] OT bad stock tips
Yup. Moving those engines forward to make clearance was a
change that really narrowed the CG box. My own thought was
to figure out a way to make the landing gear longer
without affecting the CG. Oh well. They made their bed...
bp
<part15sbs{at}gmail{dot}com>
On 11/12/2019 8:15 AM, Carl
Peterson wrote:
The newer high efficiency engines are too
big to fit under the wings. The engineers told them it
wouldn't work. The original plan was to start working
on designing a new plane, but they were afraid of losing
business to neo so the engineers were told to make it
work. In order to do this, they pushed the engines up
and mostly in front of the wing which pushed CG forward
and moved center of thrust. This lead to a plane that
needs a much narrower flight envelope, i.e it doesn't
want to fly in a lot of attitudes where a real 737 is
fine.
Why do you believe it is inherently
flawed?
It is a 737, the airframe with the best
track record on the planet.
It is too bad they did not have a
voting/contention algorithm between the two
angle of attack sensors and chose to only use
one as the authoritative source. That was a
boneheaded coding decision. The other sensor
had live data on the network that was there
for the using.
It is too bad the pilots failed to absorb
the training update telling them to switch off
the system when it was causing control inputs
that were obviously wrong.
It is too bad the pilots did not simply
switch it off. I have had runaway trim motors
try to do this to me before and that is
something you learn during primary training.
Even then, you can recover almost all
upsets with “push-power-rudder-roll-climb”.
It is too bad that Boeing did not
immediately tell operators to cease using that
system after the first crash.
But this is just one system amongst
hundreds on the aircraft, all tried and true
for many years.
Sent: Tuesday, November 12,
2019 7:18 AM
Subject: Re: [AFMUG] OT bad
stock tips
The Max is inherently flawed
and I'd generally say don't bet on things
with inherent flaws. Think F35 and how long
it took to get that kind of sort of right.
The CG is too far forward. Perhaps if they
stretched the aft section a little and swept
the wings back a little but then it wouldn't
be a 737 anymore.
I have an idea of building up a list of
ISPs with rural exposure and shorting them
because Sarlink is going to blow up a lot
of their business model. In particular,
I'd look for double play ISPs with ARPU
above about 75.
Boeing is going to have a good
year. The MAX 737 saga is coming
to an end and their while system
will be better because of it. And
then it will be forgotten. Just
like VW emissions testing...
Even so, I am going to stick
with my super high priced index
fund. It is at a historical high
and I still dumped more money into
it.
Sent: Monday,
November 11, 2019 8:26 PM
Subject: Re:
[AFMUG] OT bad stock tips
Something
like 6 months ago my financial
advisor convinced me to sell
my GM stock and buy Boeing.
I’ve suspected I did something
stupid ever since. Getting
out of GM was probably OK, but
I think Boeing has plenty of
room to drop. I am afraid
investors may dump BA as end
of year approaches to clean up
their portfolio or take tax
losses, and in any case, they
are not looking like a well
run company.
So if you
want to double down on your
Moviepass adventure, you could
buy a bunch of Boeing.
Or how
about Frontier
Communications? A bargain at
less than $1. 5 years ago
they were at $100. Bloomberg
article a couple days ago says
they are looking for a new CEO
ahead of an expected
bankruptcy filing. Which was
totally predictable when they
took on a mountain of debt to
buy all the areas that Verizon
and AT&T didn’t want. It
has to be bottoming out. No
where to go but up, right?
I
am thinking of
following up my
strategic Moviepass
investment with one in
PG&E. It has to
be bottoming out. No
where to go but up,
right?
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PORT NETWORKS
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Baltimore, MD 21202
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